Abstract: Disclosed are a rare cell capture system and an application thereof. The system comprises a fluid tube device, a circulation power apparatus device, a component capture device and an optional anticoagulant release device, the circulation power apparatus device and the component capture device being connected in series to a fluid circulation system via the fluid tube device to form an extracorporeal fluid circulation pathway, the component capture device comprising a microfluidic chip or a chipset. Also disclosed is a method for using the capture system to capture rare cells in blood. The system and the application thereof have the advantages of being large-capacity, in-line and low-hemolysis.